Lennox G14Q4 problem - long delay before blower starts, no heat until it starts
#1
04-01-12, 11:13 PM
Lennox G14Q4 problem - long delay before blower starts, no heat until it starts
If I run the fan/blower continuously, the furnace cycles on and off normally. However, if I put the blower setting on auto, once the furnace completes a cycle and reaches the set temperature, (and the blower shuts down), the furnace will not cycle back on when the temperature drops. It will restart if I shut the furnace off and switch the blower/fan setting back to continuous. However, it takes a good 5 to 10 minutes for the blower to start. Once the blower starts and I switch the furnace back on, the furnace fires up immediately.
I'm guessing that this involves the indoor blower relay...or could it be something else?
Any advice would be appreciated. I think it's been over a year since last servicing.
Mike H
I'm guessing that this involves the indoor blower relay...or could it be something else?
Any advice would be appreciated. I think it's been over a year since last servicing.
Mike H
#2
04-02-12, 12:02 PM
I would first check the thermostat. Is it getting voltage from the furnace? Sending a signal on a call for heat? What is the temperature differential set at?
#4
04-03-12, 12:47 AM
Originally Posted by goldstar
I would first check the thermostat. Is it getting voltage from the furnace? Sending a signal on a call for heat? What is the temperature differential set at?
Temperature reaches trigger point (>.75 degrees difference)
The blower setting was on automatic and the temperature had dropped below the trigger point. I heard a humming noise from furnace which lasted for > 10 minutes, then it shut down. The blower never turned on, but the exit duct work right above furnace warmed up.
I then switched the blower setting to continuous. I heard a softer humming sound from furnace, but the duct above the furnace did not heat up. The blower came on after about 10 minutes. The furnace now turns off and on normally as temperature varies.
Does this give you any more information, or do I need to drag out the multimeter and try to figure out how and where to read the voltage?
Thanks
Mike H
#5
04-03-12, 12:54 AM
Originally Posted by mbk3
Per chance is this furnace equipped with a Johnson ignition module. Such as a G67 or G76 series blue and grey colors
